My first post on Slowtwitch. :-)
I have had IT Band Syndrome in my right leg since I was a teen, I trained for my first half-marathon and marathon last year and got ITBS on the left leg too. I went to every type of doc (and got the same diagnosis everywhere), read everything on the net I could find and nothing really helped.
My advice would be: take longer steps, for most ITBS comes out on hills up and down and that is because (at least I think so) steps become shorter. If I run like the pros (really long strides, pulling my knees high and my verse high, use more of my thigh and glute muscles instead of my calf muscles) my ITBS doesn't come out.
If you train in the gym you should be able to run longer with proper form and use more muscle groups for longer.
If you run too long and you start to become tired, your steps/strides become shorter, so stick to short distances (for me that's 9km with 2km uphill running right now, on flats I can run a halfmarathon without any problems), keep an attention on your running form, if you feel weak take a couple of seconds to recover. I run twice a day, which gives my body enough time to rest and recuperate.
If it hurts too much take a week or two off.
I think that drugs that reduce inflammation are making it worse on the long term, but that is just a feeling.
For some reason cartilage drugs help me with my recovery, but I have no idea why.
Pros have long strides because they are moving faster. Their turnover is high at all speeds. If you watch them running slow, they will have very short strides. Having a slower runner use a long stride would result in very poor run mechanics.
For myself at least, my ITBS was a direct results of tight hips and calves. I'm not sure mechanically how I was compensating specifically, but ultimately not using my glutes and calves efficiently caused the issues.
When it flared, stretching, stretching and more, and more stretching resolved it. I'm talking about taking a solid 30 minutes doing 6-8 different stretches, holding them for 20 seconds or more and repeating that 3 times each stretch. Do the math, it adds up. When it was its' worst, I did that 2x a day. Chiro, massage, rolling did nothing. Almost a complete waste of time and money for me. Well, rolling might have helped just a little at least, but not on it's own.
FWIM - when you get tired, your turnover often drops and you stop driving your leg and using a less effective leg recovery. The results is lower run economy, more vertical motion, using your hamstrings and hips more. I think you have stride length a bit misunderstood. You need to consider ground contact time vs stride length as well. Look at walking, maximum ground contact vs. fast running, minimum ground contact. As a sliding scale, as you running get less efficient, strides get longer, cadence drops, ground contact increases and it's more like walking. Running involve jumping from leg to leg at a high rate and the key is recovering the energy using you Achilles and arch when landing and releasing that stored energy when you extend your leg at the end of the stride.
I do agree with using frequency and reducing the length of long runs in training. Running 6 or 7 days a week to complete the same total training load/mileage, is a great strategy.
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